/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 */

package javax.lang.model.util;

import static javax.lang.model.SourceVersion.RELEASE_6;

import javax.annotation.processing.SupportedSourceVersion;
import javax.lang.model.SourceVersion;
import javax.lang.model.type.NoType;
import javax.lang.model.type.PrimitiveType;
import javax.lang.model.type.TypeKind;
import javax.lang.model.type.TypeMirror;

/**
 * A visitor of types based on their {@linkplain TypeKind kind} with default
 * behavior appropriate for the {@link SourceVersion#RELEASE_6 RELEASE_6} source
 * version. For {@linkplain TypeMirror types} <tt><i>XYZ</i></tt> that may have
 * more than one kind, the <tt>visit<i>XYZ</i></tt> methods in this class
 * delegate to the <tt>visit<i>XYZKind</i></tt> method corresponding to the
 * first argument's kind. The <tt>visit<i>XYZKind</i></tt> methods call
 * {@link #defaultAction defaultAction}, passing their arguments to
 * {@code defaultAction}'s corresponding parameters.
 * 
 * <p>
 * Methods in this class may be overridden subject to their general contract.
 * Note that annotating methods in concrete subclasses with
 * {@link java.lang.Override @Override} will help ensure that methods are
 * overridden as intended.
 * 
 * <p>
 * <b>WARNING:</b> The {@code TypeVisitor} interface implemented by this class
 * may have methods added to it in the future to accommodate new, currently
 * unknown, language structures added to future versions of the Java&trade;
 * programming language. Therefore, methods whose names begin with
 * {@code "visit"} may be added to this class in the future; to avoid
 * incompatibilities, classes which extend this class should not declare any
 * instance methods with names beginning with {@code "visit"}.
 * 
 * <p>
 * When such a new visit method is added, the default implementation in this
 * class will be to call the {@link #visitUnknown visitUnknown} method. A new
 * type kind visitor class will also be introduced to correspond to the new
 * language level; this visitor will have different default behavior for the
 * visit method in question. When the new visitor is introduced, all or portions
 * of this visitor may be deprecated.
 * 
 * @param <R>
 *            the return type of this visitor's methods. Use {@link Void} for
 *            visitors that do not need to return results.
 * @param <P>
 *            the type of the additional parameter to this visitor's methods.
 *            Use {@code Void} for visitors that do not need an additional
 *            parameter.
 * 
 * @author Joseph D. Darcy
 * @author Scott Seligman
 * @author Peter von der Ah&eacute;
 * @since 1.6
 */
@SupportedSourceVersion(RELEASE_6)
public class TypeKindVisitor6<R, P> extends SimpleTypeVisitor6<R, P> {
	/**
	 * Constructor for concrete subclasses to call; uses {@code null} for the
	 * default value.
	 */
	protected TypeKindVisitor6() {
		super(null);
	}

	/**
	 * Constructor for concrete subclasses to call; uses the argument for the
	 * default value.
	 * 
	 * @param defaultValue
	 *            the value to assign to {@link #DEFAULT_VALUE}
	 */
	protected TypeKindVisitor6(R defaultValue) {
		super(defaultValue);
	}

	/**
	 * Visits a primitive type, dispatching to the visit method for the specific
	 * {@linkplain TypeKind kind} of primitive type: {@code BOOLEAN},
	 * {@code BYTE}, etc.
	 * 
	 * @param t
	 *            {@inheritDoc}
	 * @param p
	 *            {@inheritDoc}
	 * @return the result of the kind-specific visit method
	 */
	@Override
	public R visitPrimitive(PrimitiveType t, P p) {
		TypeKind k = t.getKind();
		switch (k) {
		case BOOLEAN:
			return visitPrimitiveAsBoolean(t, p);

		case BYTE:
			return visitPrimitiveAsByte(t, p);

		case SHORT:
			return visitPrimitiveAsShort(t, p);

		case INT:
			return visitPrimitiveAsInt(t, p);

		case LONG:
			return visitPrimitiveAsLong(t, p);

		case CHAR:
			return visitPrimitiveAsChar(t, p);

		case FLOAT:
			return visitPrimitiveAsFloat(t, p);

		case DOUBLE:
			return visitPrimitiveAsDouble(t, p);

		default:
			throw new AssertionError("Bad kind " + k + " for PrimitiveType" + t);
		}
	}

	/**
	 * Visits a {@code BOOLEAN} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsBoolean(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@code BYTE} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsByte(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@code SHORT} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsShort(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits an {@code INT} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsInt(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@code LONG} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsLong(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@code CHAR} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsChar(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@code FLOAT} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsFloat(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@code DOUBLE} primitive type by calling {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitPrimitiveAsDouble(PrimitiveType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@link NoType} instance, dispatching to the visit method for the
	 * specific {@linkplain TypeKind kind} of pseudo-type: {@code VOID},
	 * {@code PACKAGE}, or {@code NONE}.
	 * 
	 * @param t
	 *            {@inheritDoc}
	 * @param p
	 *            {@inheritDoc}
	 * @return the result of the kind-specific visit method
	 */
	@Override
	public R visitNoType(NoType t, P p) {
		TypeKind k = t.getKind();
		switch (k) {
		case VOID:
			return visitNoTypeAsVoid(t, p);

		case PACKAGE:
			return visitNoTypeAsPackage(t, p);

		case NONE:
			return visitNoTypeAsNone(t, p);

		default:
			throw new AssertionError("Bad kind " + k + " for NoType" + t);
		}
	}

	/**
	 * Visits a {@link TypeKind#VOID VOID} pseudo-type by calling
	 * {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitNoTypeAsVoid(NoType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@link TypeKind#PACKAGE PACKAGE} pseudo-type by calling
	 * {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitNoTypeAsPackage(NoType t, P p) {
		return defaultAction(t, p);
	}

	/**
	 * Visits a {@link TypeKind#NONE NONE} pseudo-type by calling
	 * {@code defaultAction}.
	 * 
	 * @param t
	 *            the type to visit
	 * @param p
	 *            a visitor-specified parameter
	 * @return the result of {@code defaultAction}
	 */
	public R visitNoTypeAsNone(NoType t, P p) {
		return defaultAction(t, p);
	}
}
